In a machine tool, when replacing a tool, or a tool holder to which the tool is attached, mounted on a main shaft, chips generated by machining sometimes attach to seating portions of the tool or tool holder and the main shaft. In a state in which the chips are caught up in the seating portions in this manner, the main shaft is not properly in close contact with the tool or the tool holder, and thus the positioning of the tool with respect to the main shaft, and specifically, the positioning of the tool with respect to the machine tool, cannot be accurately performed. Thus, if machining is performed in this state, a negative impact on machining accuracy is incurred, and there is a risk of damaging the tool or the main shaft.
A seating detection device has been developed (see Patent Document 1), which can detect whether or not the tool or the tool holder has been mounted in close contact with the main shaft. With this device, air is fed to the seating portions of the tool or the tool holder and the main shaft, and a seated state of the tool or the tool holder and the main shaft is detected through pressure changes of the air.
Further, in order to inhibit the chips from becoming caught up in the seating portions, a cleaning device has been developed that removes the chips and the like attached to the seating portions. With this means, air is fed to the seating portions of the tool or the tool holder and of the main shaft, and the chips and the like attached to the seating portions are removed by being blown away by spraying the air onto the seating portions.